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/*--------------------------------------------------
* ExclusiveChoiceGroup.java
*
* Example from the book: Core J2ME Technology
* Copyright John W. Muchow http://www.CoreJ2ME.com
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class ExclusiveChoiceGroup extends MIDlet implements ItemStateListener, CommandListener
{
private Display display; // Reference to display object
private Form fmMain; // The main form
private Command cmExit; // A Command to exit the MIDlet
private Command cmView; // View the choice selected
private ChoiceGroup cgEmail; // Choice group
private int replyIndex; // Index of "reply" in choice group
private int choiceGroupIndex; // Index of choice group on form
public ExclusiveChoiceGroup()
{
display = Display.getDisplay(this);
// Create an exclusive (radio) choice group
cgEmail = new ChoiceGroup("Email Options", Choice.EXCLUSIVE);
// Append options, with no associated images
cgEmail.append("Read", null);
replyIndex = cgEmail.append("Reply", null);
cgEmail.append("Forward", null);
cgEmail.append("Delete", null);
// Set "reply" as the default/selected option
cgEmail.setSelectedIndex(replyIndex, true);
cmExit = new Command("Exit", Command.EXIT, 1);
cmView = new Command("View", Command.SCREEN,2);
// Create Form, add components, listen for events
fmMain = new Form("");
choiceGroupIndex = fmMain.append(cgEmail);
fmMain.addCommand(cmExit);
fmMain.addCommand(cmView);
fmMain.setCommandListener(this);
}
// Called by application manager to start the MIDlet.
public void startApp()
{
display.setCurrent(fmMain);
}
public void pauseApp()
{ }
public void destroyApp(boolean unconditional)
{ }
public void commandAction(Command c, Displayable s)
{
if (c == cmView)
{
// Build a string showing which option was selected
StringItem stiMessage = new StringItem("You selected: ", cgEmail.getString(cgEmail.getSelectedIndex()));
fmMain.append(stiMessage);
// Delete the choice group & view button
fmMain.delete(choiceGroupIndex);
fmMain.removeCommand(cmView);
}
else if (c == cmExit)
{
destroyApp(false);
notifyDestroyed();
}
}
public void itemStateChanged(Item item)
{
}
}
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